库伦法测定穿心莲内酯的化学纯度  

Reseach on determination of chemical purity of andrographolide by coulometric titration method

作　　者：杨宁[1,2] 杨德智[1,2] 徐礼燊[1,2] 吕扬[1,2] 

机构地区：[1]北京协和医学院 [2]中国医学科学院药物研究所,北京100050

出　　处：《中国中药杂志》2010年第8期1014-1017,共4页China Journal of Chinese Materia Medica

基　　金：科技部科技基础性工作专项重点项目(2007FY130100);科技部科技基础性创新方法工作专项项目(2008IM022200)

摘　　要：目的:利用库伦滴定分析技术,建立一种针对穿心莲内酯化学成分的纯度检测新方法。方法:采用穿心莲内酯与溴离子间的电荷转移量,实现利用库仑滴定检测穿心莲内酯化学成分纯度目的。以4 mol.L-1盐酸-1 mol.L-1溴化钾-1mol.L-1硝酸钾1∶1∶1为电解液,阳极上电解生成的溴与穿心莲内酯发生反应,电极反应电子转移数为2。结果:穿心莲内酯化学样品的纯度值为99.76%,RSD 0.33%。利用高效液相色谱法的面积归一化法对库伦滴定新分析方法测得的纯度值进行验证,结果为99.77%,RSD 0.02%。结论:2种测定方法结果一致,表明建立的库伦滴定法的科学,可行。该法具有快速、简便、灵敏、准确和不需要用标准物质等优点,可用于测定穿心莲内酯化学物质的纯度值。The determination of chemical purity of andrographolide by coulometric titration method is studied in this paper.The coulometric titration was carried out in a mixture composed of 4 mol·L-1 hydrochloric acid and 1 mol·L-1 potassium bromide solution and 1 mol·L-1 potassium nitrate solution（1∶1）.Bromine is electrogenerated at the anode and reacts with the andrographolide.The number of electrons involved in the eleatrode reaction is 2.Purity of andrographolide is 99.76% compared with 99.77% utilizing area normalization method by HPLC.The RSD are 0.33% and 0.02% respectively.The results from two methods are consistent,so the determination of chemical purity of andrographolide by coulometric titration method is scientific and feasible.The method is rapid,simple,convenient,sensitive and accurate.The reference material is not essential in the method.The method is suitable for determination of chemical purity of andrographolide.

关 键 词：穿心莲内酯 库伦滴定法 高效液相色谱法 

分 类 号：R284.1[医药卫生—中药学]